In 2017 the all-new L5P Duramax engine made the milestone of being the 2,000,000th GM Duramax engine coming off the assembly line. The 6.6L Duramax L5P engine was a completely redesigned Duramax with a multitude of brand-new components for a significant increase in horsepower and torque. To provide GM Silverado/Sierra 2500HD/3500HD pickups a sturdier engine foundation, the block casting was changed and the engine internals were reinforced to handle the additional power output. The common-rail fuel system received many upgrades for increased fuel rail pressure that led to more efficient combustion. One of the main components linked to the enhanced power output was a new BorgWarner turbocharger. In 2017 Duramax-powered trucks also received a functional hood scoop to send additional cool and fresh air into the engine. This new generation of Duramax engines provided superior power output, low diesel emissions, and an enhanced driving experience.

While there were several brand-new features added to the 6.6L Duramax engine, the solid foundation of a deep-skirt cast-iron block with cast-aluminum heads was carried over from the previous generation with a few upgrades. The gray-iron block received an updated casting with hardened cylinder walls and was heat treated to improve its overall strength. The aluminum cylinder heads also received updated casting with improved airflow passages and double-layer coolant passages for improved durability. Inside this all-new Duramax engine was a reinforced rotating assembly. Previous generations were plagued with piston failures, which led to redesigned pistons on the L5P engine that featured taller and thicker walls for improved strength. The connecting rods still had a fractured cap design but were constructed of powdered metal with a 45-degree split angle that provided better clearance between the crankshaft. A high-capacity oil cooler was added to the L5P Duramax to provide better lubrication with the increased power output. The common-rail fuel system on the Duramax received a complete overhaul for the L5P engine. GM would no longer have Bosch supply fuel system components or ECMs for this engine. Instead, GM used a Denso HP4 injection pump with an in-tank lift pump that would provide up to 36,000 PSI of rail pressure. Paired with the new pump are Denso solenoid-style injectors with 7-hole nozzles that provided superior atomization for enhanced fuel efficiency. Upgrades to the common-rail fuel system also helped reduce emissions.

Most of the components for the emission control system carried over from the previous generation, but the EGR cooler was upgraded with an integrated throttle valve to regulate intake pressure and EGR flow rate. One of the main focuses of the L5P Duramax was increasing horsepower and torque. The main factor of that power increase was a new BorgWarner variable-geometry turbocharger. This turbocharger offered a higher flow, featured an electronic actuator, and also doubled as an exhaust brake to assist towing heavy loads. The combination of all the state-of-the-art components on the L5P Duramax led to a significant power output increase over its predecessor. In 2017 the 6.6L Duramax L5P was rated at 445 hp and 910 lb-ft of torque, which was almost a 50 hp and 150 lb-ft of torque increase over the previous generation. Coupled to this high-power diesel engine was the Allison 1000 6-speed automatic transmission. The L5P Duramax is still used in GM Silverado and Sierra 2500HD/3500HD pickups up for the 2021 model year, however it received some upgrades for the 2020 model year. If you’re looking to boost performance or maintain factory function in your L5P Duramax, Cyberpunk Diesel is sure to have what you need. Perform routine maintenance with the high-quality Fuel Filters and Oil Filters available at Cyberpunk Diesel. Make your GM Silverado/Sierra 2500HD/3500HD one-of-a-kind with all the custom accessories available at Cyberpunk Diesel. Find Lift Kits, Lighting Accessories, Exhaust Systems, and much more to fully customize your truck. Cyberpunk Diesel carries parts from hundreds of the top manufacturers to provide you with everything your 2017-2019 GM 6.6L Duramax L5P needs.